[llvm] [AssumptionCache] Don't use ResultElem for assumption list (NFC) (PR #160462)

[Ramkumar Ramachandra via llvm-commits]

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@@ -21,8 +21,8 @@ DropUnnecessaryAssumesPass::run(Function &F, FunctionAnalysisManager &FAM) {
   AssumptionCache &AC = FAM.getResult<AssumptionAnalysis>(F);
   bool Changed = false;
 
-  for (AssumptionCache::ResultElem &Elem : AC.assumptions()) {
-    auto *Assume = cast_or_null<AssumeInst>(Elem.Assume);
+  for (WeakVH &Elem : AC.assumptions()) {
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artagnon wrote:

```suggestion
  for (const WeakVH &Elem : AC.assumptions()) {
```

https://github.com/llvm/llvm-project/pull/160462